US spy base in NZ?

United States whistleblower Edward Snowden last night made sensational claims that New Zealanders were misled about the extent of mass surveillance.

The fugitive National Security Agency (NSA) analyst told a packed Auckland Town Hall that he personally had access to Kiwis' private communications through the controversial data harvesting tool X-Keyscore.

And he further claimed the NSA operates a ''facility'' in Auckland and in the north of the country.

Snowden was beamed in from Russia, where he has asylum.

He said that while he was based in Hawaii, X-Keyscore had given him the ability to use email addresses to search for private communications.

This included metadata and the content of messages.

He said not only did New Zealand's Government Communications Security Bureau (GCSB) use X-Keyscore, but the agency also contributed to its expansion and development.

However, Snowden said New Zealanders should question why the agency was investigating mass surveillance - under Project Speargun - when this would have been illegal under New Zealand law at the time.

It follows the release of a report by Greenwald, one of the recipients of the Snowden documents, which show the Five Eyes intelligence partners believed that beefed up spying legislation, introduced last year, would legally sanction wholesale spying in New Zealand.

The top-secret material shows senior intelligence official Roy Ferguson, who was based at the Department of Prime Minister and Cabinet, visited the NSA in Washington in March last year to deliver a briefing on the pending law changes.

The papers confirm the suspicions of critics of the GCSB Act, passed in August 2013, who feared the legislation would open the door to mass surveillance.

According to Greenwald, the Snowden documents show that in 2012-13, the GCSB and NSA began working on phase one of a ''mass surveillance program'' called Speargun.

This involved installing equipment that would allow access to the main undersea internet cable link, the Southern Cross Cable, Greenwald wrote on his Intercept site.

Phase two involved inserting ''meta data probes'' on to the cable, beginning in mid-2013. However, this required new legislation to be passed.

The Government introduced two new laws last year, after it emerged the GCSB illegally spied on Kiwis for more than a decade.

''Surveillance probes of this sort are commonly used by NSA and their partners to tap into huge flows of information from communication cables in real time, enabling them to extract the dates, times, senders, and recipients of emails, phone calls, and the like,'' Greenwald said.

Earlier in the day Snowden claimed in a report on Greenwald's website that while at the NSA he ''routinely'' came across the communications of New Zealanders while working in the X-Keyscore mass surveillance tool.

''If you live in New Zealand you are being watched,'' Snowden said in the report.

However, Snowden fired back, saying the company would be unaware of the NSA's moves to target it.

Key has said repeatedly that mass surveillance has never taken place, and he would resign if it was proved.

However, in a piece for Greenwald's website, Snowden wrote: ''The prime minister's claim to the public, that 'there is no and there never has been any mass surveillance', is false.

''The GCSB, whose operations he is responsible for, is directly involved in the untargeted, bulk interception and algorithmic analysis of private communications sent via internet, satellite, radio, and phone networks.''

Key has never confirmed that the GCSB has access to the programme, but Snowden said it was shared with the NSA.

''The GCSB provides mass surveillance data into X-Keyscore. They also provide access to the communications of millions of New Zealanders to the NSA at facilities such as the GCSB facility in Waihopai, and the Prime Minister is personally aware of this fact.''

Greenwald's revelations went live yesterday afternoon, before he appeared at the town hall event staged by Internet Party founder Kim Dotcom.

Key has accused the Pulitzer Prize-winning journalist of trying to sabotage the election as one of the tech mogul's ''henchmen''.